Lamp and method of making bases therefor



a. H. ROLFES.

LAMP AND METHOD OF MAKING BASES THEREFOR.

APPLICATION FILED OCT. 7, I920.

Patented Aug. 29, 1922,

GEORGE E. ROILFES, OF ST. LOUIS, MISSOURI, ASSIGNOB, TO HANDLAll-YBUCK MANU- FACTURING COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

LAMP AND METHOD 03? HEAKING BASES THEREFOR;

Specification of Letters Patent.

Patented Aug. 29, 1922,

Application filed October 7, 1920. Serial No. 4153M.

T all 7mm it may concern:

Be it lrnownthat I, GEORGE H. Homes, a citizen of the United States of America, a resident of the city of St. Louis, in the State of Missouri, have invented certain new and useful improvements in Lamps and Methods of Making Bases Therefor, of which the following is a full, clear, and ex act description, reference being had to the accompanying drawings, forming a part oi this specification,

-- some other lamps used in connection with railroad signals, have been supported by rotary stafi's, and these lamps should be firmly supported in true vertical positions. The supporting staff is usually provided with a tapered upper end, non-circular in cross section, and the lamp base has a socket in which the tapered end of the staff is inserted. it is economical to make the lamp base of ordinary cast iron, or malleable iron, but such castings are not accurate enough to properly lit the lamp supporting staffs. Heretofore it has been necessary to accurately finish the castings for the purpose of making the sockets conform to the tapering staffs, and lamp manufacturers have carried in stock numerous different castings adapted to be machined and otherwise finished to it supporting staffs of different dimensions. The cost of the labor involved in finishing these castings is an important item. and it has been very diiiicult to obtain the desired accuracy in finishing the staff-receiving sockets. The socket should firmly engage the tapered end of the supporting staif, so as to provide a firm support for the lamp, and the lamp should be supported in a true vertical position parallel with the axis of the staff.

In accordance with the resent invention, the lamp base may be an ordinary rough casting and it is not necessary to smooth the inner surfaces of the stalf-receiving socket in the rough casting. In fact, an advantage is gained by leaving these surfaces in a rough condition. Furthermore, the same pattern may be used in making base cast ings intended to receive supporting staffs of different dimensions, so it is not necessary for the lamp manufacturer to carry a large sLOCk of different base castings. k

Briefly stated, the lamp base may be an ordinary rough casting provided with a tubular mold member which may have rough inner faces. A. smooth metal. core,conformmg to the shape and dimensions of any selected 'la'inp-suppm-ting staff, is inserted into the tubular mold member, and the space between the core and the inner faces of the mold member is then filled by a body of molten metal, When this body of metal becomes cool and hard, it will be interlocked with the rough inner faces of the mold memher which forms part of the lamp base, and the entire base can be easily withdrawn from the smooth. tapering metal core. The resultant product is a lamp base having a staff receiving socket conforming precisely to the shape and dimensions ofthe upper end of the staff.

Fig. I a side elevation, partlyin section, illustrating a switch lamp embodying the features of this invention, i,

Fig, ll is an enlarged vertical section illustrating the method of forming the adapter in the lamp base. i

Fig. III is a top or plan view of the elements shown in Fig. 11.

designates the body of a switch lamp including a housing I17 provided with a bottom wall 2. B designates a base arranged below and secured to the lamp body.

The base l3 includes a central tubular mold member 3 non-circular in cross-sec tion, arms 4 extending from the upper portion of said mold member, and supporting wings 5 extending from the corners of the mold member. The lower edges of wings 5 are preferably flush with the lower edges of the mold member 3, so as to allow the lamp to be seated on' a horizontal surface when it is'not in use, The arms 4: lie within the housing 1 at points below the bottom wall 2, and said arms are secured to the housing by means of rivets 6.

The lamp base, including the mold memher 3, may be made of ordinary cast iron, or malleable iron, and the opening in the tubular mold member may be larger at the top than at the bottom of the base casting.

C designates a tubular adapter located in the mold member 3 and'provided with a non-circular tapering opening conforming,

nates a table on which the lamp base B is seated, and'D designates a metal core lo cated in the'mold member 3 of the lamp base and provided at its lower end with a circular head 8 which lies within the table 7. Centering lugs 9 are secured to the table Tatpoints on opposite sides of the core D. These lugs 9 are adapted to engage the wings 5 and mold member 3, as shown in the drawings, so as to enable the base casting tobe easily located in the proper position on the table-7. p

- To form the adapter C, molten metal is poured intothe mold member 3 while the core D is positioned as shown in Figs. H

and III. When-this metal becomes hard,

the lamp base can be very easily withdrawn from the smooth tapering metal. core D.

This core conforms to thetaperof the supporting stafl D, SO'the smooth inner face of the adapter will. accurately fit the supporting stall". The outer face 10 of the adapter C 'is in direct contact with the rough-walls 11' of the mold member 3, so the adapter is securely interlocked with the various projections and other irregularities on the rough inner face of the mold member.

I claim:

1. A lamp comprising a body, a base secured to said body, said base being provided with a mold member, a hollow adapter comprising av metal core cast'in said mold member, the outer 'faceoI" said adapter being in direct contact with the walls of said moldumember so asto secure the adapter thereto, and said adapter being provided with an opening for the receptionoi a' lamp supporting member. I

2. A lamp comprising a body, a base arranged below and secured to said body, said base including a tubular mold member non;- circular in cross-section, and a tubular adapter comprising a hollow metal core cast in said mold member, the outer face of said tubular adapter being indirect contact with the walls of said mold'member so asto secure the adapter in themold member, and said adapter being provided with a noncircular tapering opening for the reception of a lamp supportingstail.

A lamp comprising a lamp'body, a base below said body, said base including-a central tubular mold member non-circular in cross-section, arms extending from the'upper portion of said mold member and secured] to said body, supporting wings extending from the lower portion of said central mold member, and a metallic tubular adapter cast in said mold member, the outer face of said'tubular adapter being in direct contact with the walls of said mold member, aizuil SEMCl adapter being provided with anoncircular tapering opening for the reception oi? acentral' supporting staff. N .ln testnnony that I claim the" foregoing I hereunto afiix my signature.

7 I GEORGE H. noLFEs,' 

